Prevalence of premorbid personality disorder and its clinical correlates in patients with delusional disorder

The aim of this study was to investigate the presence of premorbid Personality Disorder (PD) and its relationship with clinical correlates in patients with Delusional Disorder (DD). Eighty-six outpatients with DD whose diagnoses were confirmed using the Structured Clinical Interview for DSM-IV Axis I (SCID-I) Disorders (psychosis module) were evaluated for premorbid PD utilizing the Standardized Assessment of Personality (SAP). Psychopathology was assessed using Module B of SCID-I and the Positive and Negative Syndrome Scale (PANSS); psychosocial functioning was evaluated with the Global Assessment of Functioning scale. Premorbid intelligence was assessed using the Wechsler Adult Intelligence Scale-Third Edition, vocabulary subtest. A sociodemographic-clinical questionnaire was completed. Sixty-four percent of the patients had at least one premorbid PD, the most common being paranoid PD (38.4%), followed by schizoid PD (12.8%). The presence of at least one premorbid PD was significantly associated with higher scores for psychopathology, in particular, on the affective dimension of DD symptoms. However, the presence of premorbid PD was not associated with psychosocial functioning. Each of the premorbid PD was associated with different psychopathological profiles. Premorbid PD is a relevant phenomenon in DD, given its high prevalence and comorbidity, its influence on clinical correlates and its potential ability to predict specific sub-syndromes.